import matplotlib.pyplot as plt
import numpy as np

x = 3
y = 4
pi = 3.14
theta = np.arange(0, 2*pi, pi/200)
r = np.ones(400)
r = x*np.cos(theta)+y*np.sin(theta)
# r = x*math.cos(theta)+y*math.sin(theta)

#
for i in range(3):
    plt.subplot(2, 3, i + 1)
    plt.plot(theta, r, color='red', marker='*')
    # plt.title(titles[i])
plt.show()
